A new, six-stage surgical classification system is described for shoulder-girdle resections for patients being treated by limb-sparing procedures for bone and soft-tissue tumors. The classification is based upon current concepts of oncological surgery, the structures removed, the type of resection performed, and the relationship of the resection to the glenohumeral joint, and it indicates the increasing surgical magnitude of the procedure. Data from 38 patients with an average follow-up period of 4.6 years (range, two to 8.4 years) were analyzed. Thirty-two tumors were in bone and six in soft tissue. Eighty-seven percent (33 of the 38 tumors) were malignant. Twenty-four lesions were located in the proximal humerus and 14 in the scapula. The system permitted classification of all shoulder girdle resections done in this study's institutions. The classification is proposed as a means of establishing a uniform terminology in the comparison of such data.